Fill in the blanks in units (Eg 3 u) or unit equations (Eg 1 u + 2).

Charlie, Bryan and Adam have some marbles.
After Charlie's number of marbles is doubled,
Bryan's number of marbles is increased by 6 and
Adam's number of marbles is reduced by 5,
the ratio of the number of stickers of Charlie to Bryan to Adam becomes 6 : 6 : 5.

Let the number of stickers that Adam has in the end be 5 u.

1. Number of marbles that Charlie has at first = _____
2. Number of marbles that Bryan has at first = _____
3. Number of marbles that Adam has at first = _____
4. Total number of marbles that they have at first = _____

	Charlie	Bryan	Adam
Before	3 u	6 u - 6	5 u + 5
Change	x 2	+ 6	- 5
After	6 u	6 u	5 u

(a)
Change information into units.

Number of marbles that Charlie has at first
= 6 u ÷ 2
= 3 u

(b)
Number of marbles that Bryan has at first = 6 u - 6

(c)
Number of marbles that Adam has at first = 5 u + 5

(d)
Total number of marbles that they have at first
= 3 u + 6 u - 6 + 5 u + 5
= 3 u + 6 u + 5 u - 6 + 5 
= 14 u - 1

Answer(s): (a) 3 u; (b) 6 u - 6; (c) 5 u + 5; (d) 14 u - 1